On a recommendation, I checked out the food court at the Lion Plaza at Tulley and King in San Jose this weekend. The shopping center is filled with Vietnamese shops, and has a food court with 5 counters near the Lion market. I tried xiu mai (pork meatballs served in a rich broth, at the 2nd counter from the left), duck noodle soup (5th counter), imperial rolls with shrimp on sugar cane and rice noodles (5th counter), and yams with tapioca and jelly in coconut milk (at Kim's sandwiches, outside the food court).
The xiu mai was definitely the highlight. Tender, slightly fatty meatballs, served in this incredible rich broth (not really sure what it was made from- maybe pork and fish sauce). I guess normally xiu mai is served on french bread as a sandwich, but it was fantastic in the broth- kind of a Vietnamese answer to Lion's head meatballs.
The duck noodle soup was served with a light broth, with a fish sauce and garlic mixture to pour in. The sauce gave it the kick it needed, but the duck was just ok. The imperial rolls and shrimp dish was pretty standard- I've had much better versions other places.
The yams in coconut milk desert was really nice. Kim's Sandwiches has a desert counter, with a bunch of sticky rice and fruit deserts. This one was soft yams, including some purple yams I think, with chewy jelly, a little tapioca, and sweet, thick coconut milk.
I'll definitely be heading back to try more xiu mai, and hit some of the places that I missed. The food is all cheap and the only problem was parking and traffic, both probably because of Chinese New Year.